1. Field of the Invention
This invention relates to a half-fitting prevention connector in which a pair of male and female connectors, when left in a half-fitted condition, the fitting between the two connectors is released by the resiliency or bias of a resilient member, and the male and female connectors, when completely fitted together, are positively locked relative to each other.
2. Related art
Various half-fitting prevention connectors are known. One such conventional half-fitting prevention connector is disclosed, for example, in Japanese Utility Model Unexamined Publication No. 5-81967.
As shown in FIG. 6, a pin-type connector 50 has a plurality of pin contacts 52 arranged therein, and has a pair of mounting flanges 50a formed respectively at opposite sides thereof. A socket-type connector 51 has a plurality of socket contacts 53 arranged therein, and wires 53a are connected to the socket contacts 53, respectively.
The pin-type connector 50 includes a box-shaped housing 54 having an open front side, and a guide plate 55 for guiding the fitting of the socket-type connector 51 is mounted centrally of the height within the housing 54, and divides the interior of the housing 54 into an upper portion and a lower portion. As shown in FIG. 7, within the housing 54, the pin contacts 52 extend from a rear portion toward the front side of this housing. A notch is formed in a central portion of each of opposite side plates 54a, and a forwardly-directed engagement piece portion 56 is formed integrally with the side plate 54a, and is disposed in the notch. A distal end of the engagement piece portion 56 terminates short of the front edge of the side plate 54a, and can be slightly flexed outwardly. An inwardly-directed engagement projection 56a is formed on the distal end of the engagement piece portion 56.
The socket-type connector 51 includes a box-shaped housing 57, and has such a size as to be fitted into the opening in the housing 54 of the pin-type connector 50. Pin holes 58 for respectively receiving the pin contacts 52, and a slot 59 for receiving the guide plate 55 is provided in the front side of the housing 57.
A movable cover 60 is movably fitted on the housing 57, and covers the housing 57 except front and rear end portions thereof. An opening 61 for receiving the pin-type connector 50 is formed in the front side of the movable cover 60. The opening 61 has such a size as to receive the opposite side plates 54a, a top plate 54b and a bottom plate 54c of the housing 54, but the distal ends of the engagement piece portions 56 can abut against the edge of the opening 61, thereby preventing the housing 54 from being inserted into the opening 61.
A pair of spring receiving portions (not shown) are formed respectively at opposite side portions of the movable cover 60 and hence at opposite side portions of the housing 57, and springs 64 are received respectively in the spring receiving portions as indicated in broken lines in FIG. 6, each of the springs 64 extending in the forward-backward direction. The movable cover 60 is normally urged forward (that is, left in FIG. 6) by the springs 64, and is retained by slots 65, formed through an upper wall of the movable cover 60, and projections 66 formed on the upper surface of the housing 57. An engagement groove 67 is formed in each of the opposite sides of the housing 57, and the engagement projection 56a of the engagement piece portion 56 is engaged in the associated engagement groove 67 when the two connectors are completely connected together. The engagement grooves 67 are normally concealed by the movable cover 60, and appear when the movable cover 60 is moved.
When the two connectors 50 and 51 are fitted together, the pin contacts 52 contact the socket contacts 53, respectively, and the engagement projections 56a are engaged respectively in the engagement grooves 67, as shown in FIG. 7. In this fitted condition, the springs 64 are compressed, and the engagement piece portions 56 are covered by the movable cover 60, so that the engagement projections 56a can not be disengaged respectively from the engagement grooves 67, thereby positively maintaining the connected condition.
On the other hand, when the completely-fitted condition is not achieved, that is, a half-fitted condition is encountered, the distal ends of the engagement piece portions 56 abut against the edge of the opening in the movable cover 60, and the springs 64 are compressed. Therefore, the movable cover 60 presses the engagement piece portions 56 under the influence of the springs 64, and therefore the two connectors 50 and 51 are urged away from each other, and can not be fitted together at all.
In the above connector, the half-fitting can be prevented. However, when the two connectors are to be fitted together while holding the opposite side surfaces of the movable cover 60 with the hand, the movable cover 60 fails to be moved, so that the fitting operation can not be achieved. And besides, the engagement piece portions 56 are not covered by the housing 57 in the completely-fitted condition, and therefore there has been encountered a problem that when an external force acts on the movable cover 60, the movable cover 60 can be easily moved, so that the fitted condition of the connectors can be accidentally released.